1. Field of the Invention
The invention relates to a process and device by which fossil fuels may be converted nearly nitric oxide-free into heat and transferred in a steam generator into the water or steam.
2. Description of the Prior Art
In the field of steam generator construction, steam generators heated with fossil fuels are normally equipped with a fire chamber in which the fossil fuel, which may be coal, oil or gas, is burned in a flame.
Said combustion produces at least locally temperatures which are close to the theoretical combustion temperature. Said temperatures are above the kinetic temperature for forming nitric oxides of 1300 centigrade.
This produces varying concentrations of nitric oxide in the off-gas depending on the firing principle, which may be a cyclone firing or front firing system, a combustion chamber with an elongated flame or also a fluidized bed-type firing system; however, more or less large combustion zones with nearly stoichiometric mixture formation and with a clearly notable formation of nitric oxide will always occur locally.
Now, the objective of the invention is to create at all sites or in all locations of the steam generator system conditions such that no formation of nitric oxide is possible. This requires creating in all locations conditions of such a type that the nitric oxide formation temperature of 1300.degree. C. is not exceeded in an oxidizing atmosphere.